Not only will Guitar Rig 4 be an awesome software upgrade, they are also releasing new hardware to go along with it. You now have a choice between 3 different professional quality audio interfaces to use with Guitar Rig 4. The new updated Guitar Rig KONTROL pedal, Guitar Rig Session, and Guitar Rig MOBILE (The new interfaces that is made for traveling and has the same quality as KONTROL and Session at a lower price)
The software side of Guitar Rig doesn’t only have new amps, it also has new mastering effects section and full stereo effects processing for all components. Along with all of that there is a new feature called KONTROL ROOM which is supposed to be the most powerful tool in the history of studio guitar recording. It basically allows you to run your mix through the “dream setup” of recording gear right inside your computer so your recording will be full of presence and cut through mix. This feature alone should be enough to get Guitar Rig 4 as far as I am concerned. I have had trouble get the earlier versions to cut through the mix well.
Also, the new guitar rig comes with the new Gibson DarkFire Guitar if you plan on getting one of those any time soon.
In conclusion, if you are planning on mixing in some guitars but want to have an unlimited amount of tones and effects then dont settle for anything less than Guitar Rig 4 PRO. It will have all of the tones and effects you can ever dream of, and all of the mixing features to make the guitars stand out more than ever with little to no effort!